Inductive Safety Sensors Reliably Detect Scissor Lift Position

The Application

In the production lines of the automotive industry, man and machine work closely in many places, such as along conveyor lines. Scissor lifts are used in various stages of production, from body construction to final assembly. They move car bodies to the required processing heights. This enables workers to perform tasks ergonomically and, for example, assemble the interior fittings, seats, rims, and bumpers according to customer requirements.

The Goal

The movement of scissor lifts must not become a source of danger for the people working near them. During assembly, scissor lifts automatically move to the specified working height. The system parts move against each other while the lifts adjust. To ensure that none of the workers’ body parts get caught between the system parts, work on scissor lifts can only be carried out if the lifts are locked in place. The workpiece on the table can only be released for machining when this end position is signaled.

The Solution

Inductive safety sensor at scissor lift.

Inductive safety sensors are ideal for reliable detection of the end position of scissor lifts. Two NSB15-L2M-2E2-V1-S2D2 inductive safety sensors can be used to detect the end position—one for the retracted state and one for the extended state. The sensor is SIL 2/PL d-compliant. Its space-saving design allows flexible mounting and easy integration into the scissor lift.

The Benefits

The inductive safety sensors have no dead band and therefore do not require a minimum distance to the target. Standard metal actuators or a metal part of the support structure can be used as targets. No adjustments need to be made on the target or machine part. The safety sensor is TÜV-certified and has high safety values. This means it can be directly integrated into the safety loop. In addition, the number of prescribed regular reference runs can be reduced. Instead of carrying out daily function tests, the operating intervals can be extended up to two months.

Technical Features

Compact cubic design with metal base and rotatable sensor head

LED for switching state and fault indication

Operating distance: 15 mm (flush), 20 mm (non-flush)

Applications up to Cat. 2, PL d/SIL 2 possible (can be used redundantly up to Cat. 3, PL e/SIL 3)